Log AWS API calls using boto3 event system

boto3_log.py

# see: https://boto3.amazonaws.com/v1/documentation/api/latest/guide/events.html#provide-client-params
import boto3
from botocore.client import Config
from botocore import UNSIGNED
import json


def intercept_params(params, **kwargs):
    print(
        json.dumps(
            {
                "service": kwargs.get("event_name").split(".")[-2],
                "operation": kwargs.get("event_name").split(".")[-1],
                "params": params,
                "region": kwargs.get("context")["client_region"],
            },
            indent=4,
        )
    )


if __name__ == "__main__":
    client = boto3.client("s3", config=Config(signature_version=UNSIGNED))
    client.meta.events.register("provide-client-params.*.*", intercept_params)

    client.head_bucket(Bucket="flaws.cloud")
    
    """
    expected output from intercept_params:
    {
        "service": "s3",
        "operation": "HeadBucket",
        "params": {
            "Bucket": "flaws.cloud"
        },
        "region": "us-east-1"
    }
    """